All horticultural plantings are sensitive to environmental factors of one kind or another. While trees do not generally appear to be as delicate as some other plantings, the care they receive in the years after they are transplanted from a nursery often plays a major role in determining how long the tree may live and whether it will develop into a strong and healthy tree with good prospects for enhanced longevity.
Unfortunately, trees often receive very rough treatment from caretakers and neighborhood lawnkeepers. This rough treatment can be especially damaging to a young tree which has a rather soft and undeveloped bark layer protecting the base of the tree where lawn mowers, string cutters and the like impact against these trees.
The impact of such lawn care equipment upon immature and mature trees can be extremely damaging. It can be particularly damaging to a young tree. When a blow is sustained at the base of a tree, the tissues which lie beneath the bark can be irreversibly damaged. The damage from one such impact may not kill the tree, however, it can damage the tree in such way as to decrease the ultimate health of the tree and diminish its longevity. Of particular concern is permanent damage to the vascular system in the cambium layer which is very close to the outer surface of the tree and is protected only by a thin layer of bark in immature trees. Because trees can be relatively expensive plantings, and especially because the development of a strong and healthy tree requires many years of growth during which a determination as to the general health and projected longevity of a tree is not easily made, injuries to young trees can be very troublesome.
The poor treatment which immature trees often receive can result in scar tissue from concussive impacts about the trunk of the tree over a period of many years. Such continual poor treatment often results in the premature death of the tree after a number of years of growth. It will be appreciated that it is not a simple thing to replace a tree which has grown in a particular place as many as 5 to 10 years, and that replacement of such a tree generally means beginning the process over again by transplanting another young tree, perhaps even a sapling, which like its predecessor, may never reach its intended maturity because of the failure to provide protection from lawn care equipment at the base of the tree.
This problem has been recognized in the nursery and landscape industries for years. In order to protect young trees, a wide variety of tree protectors have been used. Peace (U.S. Pat. No. 185,044) discloses a tree protector consisting of slats of wood bound together by metal bands which extend around a tree trunk. However, the materials require considerable assembly and appear to be rather inflexible. As the tree grows, the trunk can be restricted within the space provided by the tree protector, and may cause damage to the very trunk which it had previously protected. Furthermore, if an impact striking the tree protector is great enough, the tree protector itself can be forced against the tree to cause the damage it is intended to prevent.
Gilman (U.S. Pat. No. 502,559) discloses a tree protector roughly similar to that of Peace '044, providing a series of wooden slats which are bound together for wrapping around a tree.
Greene (U.S. Pat. No. 561,391) discloses a tree protector made of heavy gauge sheet metal which is extremely inflexible and would have to be removed as the tree grew older or it would irreversibly damage the trunk of the tree as it outgrew the space provided for its growth within the device. Furthermore, this device can also damage the tree if it is permitted to impact against the tree in response to forces which impact against it.
Chisolm (U.S. Pat. No. 682,031) provides yet another tree protector providing wooden slats which are bound together in a manner similar to that of the tree protectors of Peace and Gilman.
Weixler (U.S. Pat. No. 116,961) discloses a tree protector consisting of a series of flexible hoops interconnected by a plurality of resilient palings longitudinally grooved to provide biting edges. The tree protector of Weixler has a rather complicated design requiring considerable labor for assembly and also has sharp edges which will be damaging to string trimmers which are used in near proximity thereto and to the tree should the device come in contact therewith.
Georges et al. (U.S. Pat. No. 4,642,938) discloses a rigid plant protection device designed to encircle a tree. The disclosed device is a one-piece housing structure including a series of vertically extending, generally rectangular shaped ridges formed into the side wall of the housing to provide rigidity and sturdiness of construction. Unfortunately, this device consumes too much space and is inflexible so that it can impact against the tree in response to forces which impact against the device.
Other devices have also been used by those of skill in the art. The inventor has previously used ribbed drainage pipe or conduit to encircle a small tree. In order to use the ribbed conduit, a cut must be made in it which is roughly parallel to the axis thereof so that the conduit may be opened to receive the tree. Unfortunately, even when this flexible plastic conduit is used to protect the base of a small tree, a mower or a string trimmer can damage the trunk of the tree by impacting against the ribbed conduit in one of the horizontal grooves between the alternating ribs of the conduit. These ribs are oriented horizontally when encircling a base of a tree so that a flared edge of a mower housing, or a heavy duty metal string spinning around a string trimmer, can drive the groove against the tree and all the impact to be transferred directly to the tree.
Accordingly, it is clear that there has existed a long and unfulfilled need in the prior art for a tree protector which is inexpensive to manufacture and easy to assemble, is not as likely to impact adversely against the tree itself, is not restrictive so as to choke off growth once the tree has outgrown the device when the device is not removed, and provides adequate protection to protect the vascular system in the cambium beneath the bark layer. The present invention provides solutions to these and other problems and also offers other advantages over the prior art, and solves other problems associated therewith.